Clematis plant named &#39;Avalanche&#39;

ABSTRACT

A new cultivar of Clematis named ‘Avalanche’ that is characterized by bronze-purple stems, shiny green foliage with variable bronze markings, and a profuse display of white flowers in spring. In combination these traits set ‘Avalanche’ apart from all other existing varieties of Clematis known to the inventor

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a new and distinct cultivar ofClematis that is grown for use as an evergreen climber on a frame orwall, or as a ground cover, shrub, tree or container plant. The newcultivar is known botanically as a Clematis xcartmanii and will bereferred to hereinafter by the cultivar name ‘Avalanche’.

[0002] ‘Avalanche’ was bred by the inventor in 1992 by crossing thepollen parent Clematis paniculata with the seed parent Clematismannoraria. The cross was conducted in a cultivated area of Hampshire,England and ‘Avalanche’ was selected from the resulting seedlings thatflowered in 1994. Selection was based on plant vigor and flower.Panicles of cream-white flowers are produced in great profusion on theprevious seasons wood. The distinguishing characteristics of ‘Avalanche’are vigor, leaf shape and large male flowers. Pruning is not requiredwhen ‘Avalanche’ is being used as a large shrub, small tree or groundcover for a large area. However, when grown in a container or confinedarea, pruning is required immediately after flowering. Young foliage mayhave a temporary light bronze coloration when exposed to lowtemperatures, that disappears as temperatures rise. However, the colorof mature leaves is permanently suffused with bronze markings.

[0003] The closest comparison plants are Clematis xcartmanii ‘SpringSensation’ (unpatented) and Clematis xcartmanii ‘Joe’ (unpatented).‘Avalanche’ is distinguishable from both comparison plants by its largerflower and increased vigor. In addition to these traits ‘Avalanche’exhibits foliage that is wider lobed and darker green than the cultivar‘Joe’.

[0004] The first asexual propagation was accomplished in 1994 usingcuttings. The first asexual propagation was accomplished by the inventorin Hampshire, England. Since that time, under careful observation, thedistinguishing characteristics have been determined stable and uniformin successive generations.

SUMMARY OF THE INVENTION

[0005] The following represent the distinguishing characteristics of thenew Clematis cultivar ‘Avalanche’. In combination these traits set‘Avalanche’ apart from all other existing varieties of Clematis known tothe inventor. ‘Avalanche’ has not been tested under all possibleconditions and phenotypic differences may be observed with variations inenvironmental, climatic, and cultural conditions, however, without anyvariance in genotype.

[0006] 1. At maturity Clematis ‘Avalanche’ exhibits bronze-purple stemsand shiny green broad-lobed foliage with variable dark bronze markings.

[0007] 2. Clematis ‘Avalanche exhibits increased vigor over any otherClematis xcartmanii variety.

[0008] 3. In spring Clematis ‘Avalanche’ produces large cream-whiteflowers on the previous seasons wood.

[0009] 4. Clematis ‘Avalanche’ is a hardy woody climber that canwithstand temperatures of minus 10° Centigrade.

[0010] 5. Clematis ‘Avalanche’ is dioecious and male.

[0011] 6. Clematis ‘Avalanche’ is five meters in height at maturity whenunpruned.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying color photographs illustrate the distinguishingtraits of the new cultivar. The plants in the photographs are twentymonths old were grown out of doors in Hampshire, England in three-galloncontainers. The photograph on sheet 1 illustrates entire plants in bloomfrom a side perspective. The photograph on sheet 2 is a close-up view ofthe foliage. The photograph on sheet 3 is a close-up view of theflowers. All photographs are taken using conventional techniques andalthough foliage colors may appear different from actual colors due tolight reflectance, they are as accurate as possible by conventionalphotography.

BOTANICAL DESCRIPTION OF THE PLANT

[0013] The following is a detailed description of the Clematis cultivarnamed ‘Avalanche’. Data was collected in Arroyo Grande, Calif. from theinventor and from plants that were fourteen to twenty months old andgrown in three-gallon containers out of doors. Color determinations arein accordance with The Royal Horticultural Society Colour Chart exceptwhere general color terms of ordinary dictionary significance are used.The growing requirements are similar to the species.

[0014] Botanical classification: Clematis xcartmanii ‘Avalanche’.

[0015] Common name: Clematis or vase vine.

[0016] Uses: Container plant, climber for frame or wall, ground cover,shrub or small tree for large area.

[0017] Parentage: ‘Avalanche’ is a hybrid resulting from the inducedhybridization of the following plants:

[0018]Female parent.—Clematis mannoraria.

[0019]Male parent.—Clematis paniculata.

[0020] Type: Suffruticose perennial.

[0021] Vigor: Vigorous. Grows approximately 2 meters a year during thefirst two years.

[0022] Habit: Recumbent when used as a ground cover and scandent whengiven a wall or frame for support.

[0023] Height (at maturity): 5 meters in height.

[0024] Width (at maturity): 35 cm. in width.

[0025] Hardiness: Hardy to minus 10° Centigrade.

[0026] Propagation: Cuttings.

[0027] Root system: Fibrous.

[0028] Soil: Plant in well-drained humus-rich soils with adequatemoisture.

[0029] Sunlight: Plant in semi-shade to full sun.

[0030] Plant sexuality: Dioecious.

[0031] Time to initiate roots: 6-8 weeks are required to produce rootson an initial cutting.

[0032] Crop time: Approximately 14 months are required to produce afinished three-gallon container from a rooted cutting.

[0033] Seasonal interest: Cream-white flowers in spring.

[0034] Stem:

[0035]Branching arrangement.—Divaricate.

[0036]Branching habit.—Recumbent on the ground and scandent withsupport.

[0037]Internode length.—10-13 cm. between nodes.

[0038]Stem diameter.—0.50 cm. in diameter.

[0039]Primary stem length.—120 cm. long.

[0040]Secondary stem length.—14 cm. in length.

[0041]Shape.—Cylindrical and fluted.

[0042]Surface.—Strigose.

[0043]Primary stem color.—200A.

[0044]Secondary stem color.—183A.

[0045]Trunk dimensions.—5 cm. in height from surface of soil and 1 cm.in width.

[0046]Trunk color.—200A.

[0047] Foliage:

[0048]Type.—Evergreen.

[0049]Leaf arrangement.—Opposite.

[0050]Leaf division.—Bitemate.

[0051]Leaf shape.—Trifoliate and slightly depressed along mid-veincreating a V-shape in cross-section.

[0052]Leaf base.—Rounded.

[0053]Leaf apex.—Apiculate and mucro at tips of mature lobes.

[0054]Leaf venation.—Pinnate with prominent mid-vein.

[0055]Vein color (adaxial surface).—137A.

[0056]Vein color (abaxial surface).—137A.

[0057]Leaf surface (adaxial).—Glabrous and shiny.

[0058]Leaf surface (abaxial).—Glabrous and matte.

[0059]Leaf attachment.—Petiolate.

[0060]Petiole dimensions.—6-10 mm. in length and 1.5 mm. in diameter.

[0061]Petiole color.—166A.

[0062]Petiole shape.—Tortuous when plant is used as a climber.

[0063]Leaf margin.—Entire.

[0064]Leaf texture.—Thick and leather-like.

[0065]Leaf length.—3-4 cm. in length.

[0066]Leaf width.—2-3 cm. in width.

[0067]Young leaf color (adaxial surface).—136B,C.

[0068]Young leaf color (abaxial surface).—137B.

[0069]Young leaf color (margin and apex).—183A.

[0070]Mature leaf color (adaxial surface).—166A suffused over 136B,C.

[0071]Mature leaf color (abaxial surface).—166A suffused over 136B,C.

[0072]Foliar fragrance.—Absent.

[0073] Flower:

[0074]Inflorescence.—Panicle.

[0075]Flower form.—Solitary.

[0076]Color of peduncle.—144A.

[0077]Peduncle length.—8.5 cm. in length.

[0078]Peduncle diameter.—0.20 cm. in diameter.

[0079]Self cleaning or persistent.—Self cleaning.

[0080]Dimensions of flower.—7.50 cm. in length and 7.50 cm. in width and1 cm. in depth.

[0081]Flower shape.—Discoid.

[0082]Flower sexuality.—Male.

[0083]Aspect.—Facing upward.

[0084]Petals.—Apetalous.

[0085]Tepals.—Six in number.

[0086]Color of tepals.—155C.

[0087]Tepal shape.—Obovate.

[0088]Tepal surface.—Undulate.

[0089]Tepal margin.—Entire with a notched apex and lateral marginsinvolute.

[0090]Tepal length.—3.5 cm. in length.

[0091]Tepal width.—2 cm.in width.

[0092]Unfused or fused.—Tepals are unfused.

[0093]Blooming period.—April to May.

[0094]Bud color.—145B.

[0095]Bud shape.—Oval.

[0096]Bud dimensions.—2 cm. in length and 1 cm. in width.

[0097]Quantity of flowers.—Approximately 11 per stem.

[0098]Fragrance.—Faintly sweet.

[0099] Reproduction organs:

[0100]Stamens.—Sixty or more.

[0101]Arrangement of stamens.—Spirally arranged.

[0102]Color of stamens.—145A.

[0103]Dimensions of stamen.—9 mm. in length and 1.5-2 mm in diameter.

[0104]Dimensions of anther.—1 mm. in width and 1 mm. in length.

[0105]Pollen color.—157A.

[0106]Anther.—2 mm. in length and 1.5 mm. in width.

[0107]Anther color.—157A.

[0108]Anther shape.—Flattened.

[0109] Seed: Seed production has not been observed.

1. A new and distinct variety of Clematis plant named ‘Avalanche’ asdescribed and illustrated.